Effects of Age on Dual-Task Walking While Listening

The impact of cognitive-motor interference on balance and gait in hearing-impaired older adults: a systematic review

BACKGROUND

Hearing impairments are a rising burden in our aging society. Hearing loss is associated with reduced cognitive performance as well as decrements in balance and gait. Therefore, impaired hearing affects also dual tasking (DT). The aim of this review is to summarize the evidence for DT performance decrements of older adults with hearing impairments during maintaining balance or walking.

METHODS

The systematic literature research according to PRISMA guidelines was conducted using MEDLINE, APA Psych-Info, and Web of Science. Inclusion criteria were: Independent living older people ≥ 60 years with hearing impairments, use of a DT paradigm to test hearing impaired older adults within a balance or walking condition.

RESULTS

N = 57 studies were found within the databases. Eight studies were included (N = 456 participants (58% women), including n = 200 older hearing-impaired persons with different levels of hearing loss). Most of the included studies oriented their inclusion criteria for hearing-impairments at thresholds for mild hearing loss with Pure Tone Average (0.5-4 kHz) ≥ 25 and < 40 dB. Three of the studies focused on DT balance performance and five used DT walking comparing participants with and without hearing loss. For DT balance and gait performance, higher decrements for the hearing-impaired group were observed compared to healthy older adults. Performance decrements were accompanied by reduced compensatory strategies in balance performance.

CONCLUSION

More pronounced decrements in DT performance were observed for participants with hearing impairments compared to those without. This implies that hearing-impaired older adults might need specific interventions to reduce the cognitive-motor interference (CMI) to maintain balance control or walking stability in daily situations that require managing of cognitive and motor tasks simultaneously. However, taking all results into account the underlying mechanisms of CMI for this target group needs to be further examined.

TRIAL REGISTRATION

This review was registered at Prospero with the ID CRD42022340232.

Effect of dual-task training on balance in older adults: A systematic review and meta-analysis

PURPOSE

Our review aims to analyze the effect of dual-task training (DTT) on balance in healthy older adults.

METHODS

PubMed, EbscoHost, Web of Science (WOS), Scopus, Cochrane Library, MEDLINE, EBSCO Open Dissertations, ULAKBIM (TR Index) and YOK (Council of Higher Education Thesis Center) databases and the gray literature were searched. The quality of the studies was assessed with the Cochrane Risk of Bias tool and statistical analysis of the data was performed with Comprehensive Meta-Analysis (CMA) software. A funnel plot and Egger's test were used to detect publication bias. Fourteen studies with 691 participants were included.

RESULTS

According to the results of our study, DTT was found to have a significant benefit on balance in older adults than the non-intervention group (standardized mean difference (SMD): -0.691: -1.153, -0.229, 95 % confidence interval (CI)). Furthermore, DTT was superior to different intervention groups in improving balance in older adults (SMD: -0.229: -0.441, -0.016, 95 % CI).

CONCLUSION

The findings of this review suggest that DTT may be an effective intervention to improve balance in healthy older adults.

Factors influencing gait performance in older adults in a dual-task paradigm

The aim of this study was to determine the effect of cognitive interference through a dual-task (DT) paradigm on gait parameters by sex or other predictive variables, such as physical fitness, health status, and cognition. A total of 125 older adults joined in this study (age, 72.42 ± 5.56 years old; 28 men and 97 women). The DT paradigm was evaluated through Comfortable Linear Gait (CLG) and Complex Gait Test (CGT). The gait parameters between single task (ST) vs. DT condition in men showed a significant reduction in speed (p < 0.001), cadence (p < 0.001), and step length (p = 0.049) and increased time to execute the CGT (p < 0.001), while women showed a decreased speed (p = 0.014), cadence (p < 0.001), and double support coefficient variation (CV) (p = 0.024) and increased single support time (p < 0.001) and CV step length (p < 0.05). In addition, women increased CGT time (p < 0.001). Furthermore, correlations between DT cost (DTC) cadence vs. Physical Activity for Elderly questionnaire (PASE) (r =  - 0.399; p = 0.008), DTC single support vs. 30 s Sit to Stand Test (r = - 0.356; 0.016), DTC single support vs. Rey Auditory Verbal Learning Test-Learning curve (r =  - 0.335; p = 0.023), DTC double support vs. 30 s Sit to Stand Test (r =  - 0.590; p < 0.001), DTC CV step length vs. 30 s Sit to Stand (r =  - 0.545; p = 0.003), and DTC CGT vs. 30 s Sit to Stand Test (r =  - 0.377; p = 0.048) were found. The results of our study indicate that the gait parameters within the DT condition decreased speed and cadence, while increasing CV step length and CGT time, causing slower gait with shortened steps in men and women.

The effect of motor resource suppression on speech perception in noise in younger and older listeners: An online study

Speech motor resources may be recruited to assist challenging speech perception in younger normally hearing listeners, but the extent to which this occurs for older adult listeners is unclear. We investigated if speech motor resources are also recruited in older adults during speech perception. Specifically, we investigated if suppression of speech motor resources via sub-vocal rehearsal affects speech perception compared to non-speech motor suppression (jaw movement) and passive listening. Participants identified words in speech-shaped noise at signal-to-noise ratios (SNRs) from -16 to +16 dB in three listening conditions during which participants: (1) opened and closed their jaw (non-speech movement); (2) sub-vocally mimed 'the' (articulatory suppression); (3) produced no concurrent movement (passive listening). Data from 46 younger adults (M age = 20.17 years, SD = 1.61, 36 female) and 41 older adults (M age = 69 years, SD = 5.82, 21 female) were analysed. Linear mixed effects modelling investigated the impact of age, listening condition, and self-reported hearing ability on speech perception (d' prime). Results indicated that speech perception ability was significantly worse in older adults relative to younger adults across all listening conditions. A significant interaction between age group and listening condition indicated that younger adults showed poorer performance during articulatory suppression compared to passive listening, but older adults performed equivalently across conditions. This finding suggests that speech motor resources are less available to support speech perception in older adults, providing important insights for auditory-motor integration for speech understanding and communication in ageing.

At-home computerized executive-function training to improve cognition and mobility in normal-hearing adults and older hearing aid users: a multi-centre, single-blinded randomized controlled trial

BACKGROUND

Hearing loss predicts cognitive decline and falls risk. It has been argued that degraded hearing makes listening effortful, causing competition for higher-level cognitive resources needed for secondary cognitive or motor tasks. Therefore, executive function training has the potential to improve cognitive performance, in turn improving mobility, especially when older adults with hearing loss are engaged in effortful listening. Moreover, research using mobile neuroimaging and ecologically valid measures of cognition and mobility in this population is limited. The objective of this research is to examine the effect of at-home cognitive training on dual-task performance using laboratory and simulated real-world conditions in normal-hearing adults and older hearing aid users. We hypothesize that executive function training will lead to greater improvements in cognitive-motor dual-task performance compared to a wait-list control group. We also hypothesize that executive function training will lead to the largest dual-task improvements in older hearing aid users, followed by normal-hearing older adults, and then middle-aged adults.

METHODS

A multi-site (Concordia University and KITE-Toronto Rehabilitation Institute, University Health Network) single-blinded randomized controlled trial will be conducted whereby participants are randomized to either 12 weeks of at-home computerized executive function training or a wait-list control. Participants will consist of normal-hearing middle-aged adults (45-60 years old) and older adults (65-80 years old), as well as older hearing aid users (65-80 years old, ≥ 6 months hearing aid experience). Separate samples will undergo the same training protocol and the same pre- and post-evaluations of cognition, hearing, and mobility across sites. The primary dual-task outcome measures will involve either static balance (KITE site) or treadmill walking (Concordia site) with a secondary auditory-cognitive task. Dual-task performance will be assessed in an immersive virtual reality environment in KITE's StreetLab and brain activity will be measured using functional near infrared spectroscopy at Concordia's PERFORM Centre.

DISCUSSION

This research will establish the efficacy of an at-home cognitive training program on complex auditory and motor functioning under laboratory and simulated real-world conditions. This will contribute to rehabilitation strategies in order to mitigate or prevent physical and cognitive decline in older adults with hearing loss.

TRIAL REGISTRATION

Identifier: NCT05418998. https://clinicaltrials.gov/ct2/show/NCT05418998.

An Exploratory Study of Walking, Listening, and Remembering in Younger and Middle-Aged Adults

PURPOSE

The purpose of this study was to assess how needing to listen and remember information while walking affects speech perception, memory task performance, and gait in younger and middle-aged adults.

METHOD

Four gait parameters (stride duration, step variability, whole-body center of mass acceleration, and mediolateral head acceleration) were measured when younger and middle-aged participants stood or walked on a treadmill while they simultaneously completed a speech-on-speech perception task and a preload memory task, singly and in combination.

RESULTS

Speech perception was significantly poorer for middle-aged than for younger participants. Performance on the speech perception measure did not differ significantly between walking and standing for either group of participants, but the additional cognitive load of the memory task reduced performance on the speech perception task. Memory task performance was significantly poorer when combined with the speech perception task than when measured in isolation for both participant groups, but no further declines were noted when participants were also walking. Mediolateral head acceleration, which has been linked to loss of balance, was significantly greater during multitask trials, as compared to when participants were only walking without being required to listen or remember. Post hoc analysis showed that dual- and multitask influences on mediolateral head acceleration were more prominent for middle-aged than for younger participants. Stride duration was longer in the multitask condition than when participants were only walking.

CONCLUSIONS

Results of this exploratory study indicate that gait may be impacted when individuals (both younger and middle-aged) are listening and remembering while walking. Data also substantiate prior findings of early age-related declines in the perception of speech in the presence of understandable speech maskers.

The association of executive functions and physical fitness with cognitive-motor multitasking in a street crossing scenario

Age-related decline in cognitive-motor multitasking performance has been attributed to declines in executive functions and physical fitness (motor coordinative fitness and cardiovascular fitness). It has been suggested that those cognitive and physical resources strongly depend on lifestyle factors such as long-term regular physical activity and cognitive engagement. Although research suggests that there is covariation between components of executive functions and physical fitness, the interdependence between these components for cognitive-motor multitasking performance is not yet clear. The aim of the study was to examine the contribution and interrelationship between executive functions, motor coordinative fitness, and cardiovascular fitness on street crossing while multitasking. We used the more ecologically valid scenario to obtain results that might be directly transferable to daily life situation. Data from 50 healthy older adults (65-75 years, 17 females, recruited in two different cities in Germany) were analyzed. Participants' executive functions (composite score including six tests), motor coordinative fitness (composite score including five tests), and cardiovascular fitness (spiroergometry), as well as their street crossing performance while multitasking were assessed. Street crossing was tested under single-task (crossing a two-line road), and multitask conditions (crossing a two-line road while typing numbers on a keypad as simulation of mobile phone use). Street crossing performance was assessed by use of cognitive outcomes (typing, crossing failures) and motor outcomes (stay time, crossing speed). Linear mixed-effects models showed beneficial main effects of executive functions for typing (p = 0.004) and crossing failures (p = 0.023), and a beneficial main effect of motor coordinative fitness for stay time (p = 0.043). Commonality analysis revealed that the proportion of variance commonly explained by executive functions, motor coordinative fitness, and cardiovascular fitness was small for all street crossing outcomes. For typing and crossing failures (cognitive outcomes), the results further showed a higher relative contribution of executive functions compared to motor coordinative fitness and cardiovascular fitness. For stay time (motor outcome), the results correspondingly revealed a higher relative contribution of motor coordinative fitness compared to executive functions and cardiovascular fitness. The findings suggest that during cognitive-motor multitasking in everyday life, task performance is determined by the components of executive functions and physical fitness related to the specific task demands. Since multitasking in everyday life includes cognitive and motor tasks, it seems to be important to maintain both executive functions and physical fitness for independent living up to old age.

Time estimation during motor activity

Several studies on time estimation showed that the estimation of temporal intervals is related to the amount of attention devoted to time. This is explained by the scalar timing theory, which assumes that attention alters the number of pulses transferred by our internal clock to an accumulator that keeps track of the elapsed time. In a previous study, it was found that time underestimation during cognitive-demanding tasks was more pronounced while walking than while sitting, whereas no clear motor-induced effects emerged without a concurrent cognitive task. What remains unclear then is the motor interference itself on time estimation. Here we aim to clarify how the estimation of time can be influenced by demanding motor mechanisms and how different motor activities interact with concurrent cognitive tasks during time estimation. To this purpose, we manipulated simultaneously the difficulty of the cognitive task (solving arithmetic operations) and the motor task. We used an automated body movement that should require no motor or mental effort, a more difficult movement that requires some motor control, and a highly demanding movement requiring motor coordination and attention. We compared the effects of these three types of walking on time estimation accuracy and uncertainty, arithmetic performance, and reaction times. Our findings confirm that time estimation is affected by the difficulty of the cognitive task whereas we did not find any evidence that time estimation changes with the complexity of our motor task, nor an interaction between walking and the concurrent cognitive tasks. We can conclude that walking, although highly demanding, does not have the same effects as other mental tasks on time estimation.

Age-related changes to vestibular heave and pitch perception and associations with postural control

Falls are a common cause of injury in older adults (OAs), and age-related declines across the sensory systems are associated with increased falls risk. The vestibular system is particularly important for maintaining balance and supporting safe mobility, and aging has been associated with declines in vestibular end-organ functioning. However, few studies have examined potential age-related differences in vestibular perceptual sensitivities or their association with postural stability. Here we used an adaptive-staircase procedure to measure detection and discrimination thresholds in 19 healthy OAs and 18 healthy younger adults (YAs), by presenting participants with passive heave (linear up-and-down translations) and pitch (forward-backward tilt rotations) movements on a motion-platform in the dark. We also examined participants' postural stability under various standing-balance conditions. Associations among these postural measures and vestibular perceptual thresholds were further examined. Ultimately, OAs showed larger heave and pitch detection thresholds compared to YAs, and larger perceptual thresholds were associated with greater postural sway, but only in OAs. Overall, these results suggest that vestibular perceptual sensitivity declines with older age and that such declines are associated with poorer postural stability. Future studies could consider the potential applicability of these results in the development of screening tools for falls prevention in OAs.

Dual-Task Performance in Hearing-Impaired Older Adults-Study Protocol for a Cross-Sectional Mobile Brain/Body Imaging Study

Background: Hearing impairments are associated with reduced walking performance under Dual-task (DT) conditions. Little is known about the neural representation of DT performance while walking in this target group compared to healthy controls or younger adults. Therefore, utilizing the Mobile Brain/Body Imaging approach (MoBI), we aim at gaining deeper insights into the brain dynamics underlying the interaction of cognitive and motor processes during different DT conditions (visual and auditory) controlling for age and the potential performance decrements of older adults with hearing impairments.

Methods: The cross-sectional study integrates a multifactorial mixed-measure design. Between-subject factors grouping the sample will be age (younger vs. older adults) and hearing impairment (mild vs. not hearing impaired). The within-subject factors will be the task complexity (single- vs. DT) and cognitive task modality (visual vs. auditory). Stimuli of the cognitive task will vary according to the stimulus modality (visual vs. auditory), presentation side (left vs. right), and presentation-response compatibility (ipsilateral vs. contralateral). Analyses of DT costs and underlying neuronal correlates focus either on gait or cognitive performance. Based on an a priori sample size calculation 96 (48 healthy and 48 mildly hearing impaired) community-dwelling older adults (50–70 years) and 48 younger adults (20–30 years) will be recruited. Gait parameters of speed and rhythm will be captured. EEG activity will be recorded using 64 active electrodes.

Discussion: The study evaluates cognitive-motor interference (CMI) in groups of young and older adults as well as older adults with hearing impairment. The underlying processes of the interaction between motor and cognitive tasks will be identified at a behavioral and neurophysiological level comparing an auditory or a visual secondary task. We assume that performance differences are linked to different cognitive-motor processes, i.e., stimulus input, resource allocation, and movement execution. Moreover, for the different DT conditions (auditory vs. visual) we assume performance decrements within the auditory condition, especially for older, hearing-impaired adults. Findings will provide evidence of general mechanisms of CMI (ST vs. DT walking) as well as task-specific effects in dual-task performance while over ground walking.

Role of age and sex on dual tasking using a treadmill desk while performing cognitive tests

BACKGROUND

Treadmill desks have been used extensively to increase physical activity and decrease sedentary time in the work environment. However, dual tasking, such as simultaneously walking and performing a cognitive task, may result in diminished performance in one or both tasks.

RESEARCH QUESTION

Do age and sex impact ability to dual task while using a treadmill desk at a preferred walking speed?.

METHODS

A total of n = 24 younger (range of 18-24 years, mean age = 21.1 ± 1.6 years) and n = 25 older (range of 45-65 years, mean age = 53.0 ± 5.1 years) adults self-selected a comfortable walking speed ranging from 0.5 to 2.0 mph and performed the Stroop Color & Word test (measuring Inhibition) and the Sternberg Test of Working Memory (measuring Working Memory) while walking at their chosen speed on a treadmill desk and while seated. Testing was performed in two separate sessions with the order counterbalanced. Step length, stride length, gait cycle time, and coefficient of variation (CV) for each were measured using OptoGait software, and both reaction time and accuracy for the two cognitive tests were assessed. Dual Task Cost (DTC) was calculated by using the formula (Single task score - Dual task score)/Single task score)*100.

RESULTS

Younger adults had faster reaction time compared to older adults for both Working Memory and Inhibition tests (p < 0.05), and both males and females had slower reaction time for the Working Memory test when seated compared to walking (p < 0.05). For DTC, older adults had greater stride length CV during the Working Memory task (32.0 % vs 19.6 %), and regardless of age or sex, DTC for gait was greater than for cognition.

SIGNIFICANCE

These data provide evidence that while aging does decrease reaction time while dual tasking, few age differences and no sex differences were found in dual task cost. However, dual tasking results in diminished gait DTC compared to cognition DTC regardless of age or sex.

Vestibular Perceptual Thresholds in Older Adults With and Without Age-related Hearing Loss

OBJECTIVES

Older adults with age-related hearing loss (ARHL) are at greater risk of falling and have greater mobility problems than older adults with normal hearing (NH). The underlying cause of these associations remains unclear. One possible reason is that age-related declines in the vestibular system could parallel those observed in the auditory system within the same individuals. Here, we compare the sensitivity of vestibular perceptual abilities (psychophysics), vestibular end-organ functioning (vestibular evoked myogenic potentials and video head impulse tests), and standing balance (posturography) in healthy older adults with and without ARHL.

DESIGN

A total of 46 community-dwelling older adults, 23 with ARHL and 23 with NH, were passively translated in heave (up and down) and rotated in pitch (tilted forward and backward) in the dark using a motion platform. Using an adaptive staircase psychophysical procedure, participants' heave and pitch detection and discrimination thresholds were determined. In a posturography task, participants' center of pressure (COP) path length was measured as they stood on a forceplate with eyes open and closed, on firm and compliant surfaces, with and without sound suppression. Baseline motor, cognitive, and sensory functioning, including vestibular end-organ function, were measured.

RESULTS

Individuals with ARHL were less sensitive at discriminating pitch movements compared to older adults with NH. Poorer self-reported hearing abilities were also associated with poorer pitch discrimination. In addition to pitch discrimination thresholds, lower pitch detection thresholds were significantly associated with hearing loss in the low-frequency range. Less stable standing balance was significantly associated with poorer vestibular perceptual sensitivity.

DISCUSSION

These findings provide evidence for an association between ARHL and reduced vestibular perceptual sensitivity.

Postural Control While Listening in Younger and Middle-Aged Adults

OBJECTIVES

The motivation for this research is to determine whether a listening-while-balancing task would be sensitive to quantifying listening effort in middle age. The premise behind this exploratory work is that a decrease in postural control would be demonstrated in challenging acoustic conditions, more so in middle-aged than in younger adults.

DESIGN

A dual-task paradigm was employed with speech understanding as one task and postural control as the other. For the speech perception task, participants listened to and repeated back sentences in the presence of other sentences or steady-state noise. Targets and maskers were presented in both spatially-coincident and spatially-separated conditions. The postural control task required participants to stand on a force platform either in normal stance (with feet approximately shoulder-width apart) or in tandem stance (with one foot behind the other). Participants also rated their subjective listening effort at the end of each block of trials.

RESULTS

Postural control was poorer for both groups of participants when the listening task was completed at a more adverse (vs. less adverse) signal-to-noise ratio. When participants were standing normally, postural control in dual-task conditions was negatively associated with degree of high-frequency hearing loss, with individuals who had higher pure-tone thresholds exhibiting poorer balance. Correlation analyses also indicated that reduced speech recognition ability was associated with poorer postural control in both single- and dual-task conditions. Middle-aged participants exhibited larger dual-task costs when the masker was speech, as compared to when it was noise. Individuals who reported expending greater effort on the listening task exhibited larger dual-task costs when in normal stance.

CONCLUSIONS

Listening under challenging acoustic conditions can have a negative impact on postural control, more so in middle-aged than in younger adults. One explanation for this finding is that the increased effort required to successfully listen in adverse environments leaves fewer resources for maintaining balance, particularly as people age. These results provide preliminary support for using this type of ecologically-valid dual-task paradigm to quantify the costs associated with understanding speech in adverse acoustic environments.

Task specificity impacts dual-task interference in older adults

BACKGROUND

Task prioritization is an important factor determines the magnitude and direction of dual-task interference in older adults. Greater dual-task cost during walking may lead to falling, sometimes causing lasting effects on mobility.

AIMS

We investigated dual-task interference for walking and cognitive performance.

METHODS

Twenty healthy, older adults (71 ± 5 years) completed three cognitive tasks: letter fluency, category fluency, and serial subtraction during seated and walking conditions on a self-paced treadmill for 3 min each, in addition to walking only condition. Walking speed, step length and width were measured during walking and each dual-task condition.

RESULTS

Comparing the percentage of correct answers in cognitive tasks across single and dual-task conditions, there was a main effect of cognitive task (p = 0.021), showing higher scores during letter fluency compared to serial subtraction (p = 0.011). Step width was significantly wider during dual-task letter fluency compared to walking alone (p = 0.003), category fluency (p = 0.001), and serial subtraction (p = 0.007).

DISCUSSION

During both fluency tasks, there was a cost for gait and cognition, with category showing a slightly higher cognitive cost compared to letter fluency. During letter fluency, to maintain cognitive performance, gait was sacrificed by increasing step width. During serial subtraction, there was a cost for gait, yet a benefit for cognitive performance.

CONCLUSION

Differential effect of cognitive task on dual-task performance is critical to be understood in designing future research or interventions to improve dual-task performance of most activities of daily living.

Simple Smartphone-Based Assessment of Gait Characteristics in Parkinson Disease: Validation Study

Background

Parkinson disease (PD) is a common movement disorder. Patients with PD have multiple gait impairments that result in an increased risk of falls and diminished quality of life. Therefore, gait measurement is important for the management of PD.

Objective

We previously developed a smartphone-based dual-task gait assessment that was validated in healthy adults. The aim of this study was to test the validity of this gait assessment in people with PD, and to examine the association between app-derived gait metrics and the clinical and functional characteristics of PD.

Methods

Fifty-two participants with clinically diagnosed PD completed assessments of walking, Movement Disorder Society Unified Parkinson Disease Rating Scale III (UPDRS III), Montreal Cognitive Assessment (MoCA), Hamilton Anxiety (HAM-A), and Hamilton Depression (HAM-D) rating scale tests. Participants followed multimedia instructions provided by the app to complete two 20-meter trials each of walking normally (single task) and walking while performing a serial subtraction dual task (dual task). Gait data were simultaneously collected with the app and gold-standard wearable motion sensors. Stride times and stride time variability were derived from the acceleration and angular velocity signal acquired from the internal motion sensor of the phone and from the wearable sensor system.

Results

High correlations were observed between the stride time and stride time variability derived from the app and from the gold-standard system (r=0.98-0.99, P<.001), revealing excellent validity of the app-based gait assessment in PD. Compared with those from the single-task condition, the stride time (F_1,103=14.1, P<.001) and stride time variability (F_1,103=6.8, P=.008) in the dual-task condition were significantly greater. Participants who walked with greater stride time variability exhibited a greater UPDRS III total score (single task: β=.39, P<.001; dual task: β=.37, P=.01), HAM-A (single-task: β=.49, P=.007; dual-task: β=.48, P=.009), and HAM-D (single task: β=.44, P=.01; dual task: β=.49, P=.009). Moreover, those with greater dual-task stride time variability (β=.48, P=.001) or dual-task cost of stride time variability (β=.44, P=.004) exhibited lower MoCA scores.

Conclusions

A smartphone-based gait assessment can be used to provide meaningful metrics of single- and dual-task gait that are associated with disease severity and functional outcomes in individuals with PD.

Functional Gait Can Be Affected by Noise: Effects of Age and Cognitive Function: A Pilot Study

Background: The ageing process may degrade an individual's balance control, hearing capacity, and cognitive function. Older adults perform worse on simultaneously executed balance and secondary tasks (i.e., dual-task performance) than younger adults and may be more vulnerable to auditory distraction.

Aim: The purpose of this study was to determine the effect of passive listening on functional gait in healthy older vs. younger adults, and to investigate the effect of age, functional gait, hearing ability and cognitive functioning on dual-task performance.

Methods: Twenty young and 20 older healthy adults were recruited. Functional gait (Functional Gait Assessment in silent and noisy condition), hearing function (audiogram; Speech in Babble test), and cognitive ability (Cambridge Neuropsychological Test Automated Battery) were measured.

Results: Overall, a significant difference between functional gait performance in silent vs. noisy conditions was found (p = 0.022), with no significant difference in dual-task cost between the two groups (p = 0.11). Correlations were found between increasing age, worse functional gait performance, poorer hearing capacity and lower performance on cognitive function tasks. Interestingly, worse performance on attention tasks appeared to be associated with a worse functional gait performance in the noisy condition.

Conclusion: Passive listening to multi-talker babble noise can affect functional gait in both young and older adults. This effect could result from the cognitive load of the babble noise, due to the engagement of attention networks by the unattended speech.

Cognitive Involvement in Balance, Gait and Dual-Tasking in Aging: A Focused Review From a Neuroscience of Aging Perspective

A substantial corpus of evidence suggests that the cognitive involvement in postural control and gait increases with aging. A large portion of such studies were based on dual-task experimental designs, which typically use the simultaneous performance of a motor task (e.g., static or dynamic balancing, walking) and a continuous cognitive task (e.g., mental arithmetic, tone detection). This focused review takes a cognitive neuroscience of aging perspective in interpreting cognitive motor dual-task findings. Specifically, we consider the importance of identifying the neural circuits that are engaged by the cognitive task in relation to those that are engaged during motor task performance. Following the principle of neural overlap, dual-task interference should be greatest when the cognitive and motor tasks engage the same neural circuits. Moreover, the literature on brain aging in general, and models of dedifferentiation and compensation, in particular, suggest that in cognitive motor dual-task performance, the cognitive task engages different neural substrates in young as compared to older adults. Also considered is the concept of multisensory aging, and the degree to which the age-related decline of other systems (e.g., vision, hearing) contribute to cognitive load. Finally, we discuss recent work on focused cognitive training, exercise and multimodal training of older adults and their effects on postural and gait outcomes. In keeping with the principle of neural overlap, the available cognitive training research suggests that targeting processes such as dividing attention and inhibition lead to improved balance and gait in older adults. However, more studies are needed that include functional neuroimaging during actual, upright performance of gait and balance tasks, in order to directly test the principle of neural overlap, and to better optimize the design of intervention studies to improve gait and posture.